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71.
Keshri Nath Tiwari Darshana Bora Garima Chauhan Deepika Yadav Kavita Sharma Ashima Thakur 《合成通讯》2016,46(7):620-625
An efficient and greener protocol for easy access to 3-susbstituted-3-hydroxy-2-oxindoles by the reaction with various substituted isatins and acetophenones is described. This protocol is widely applicable for a variety of isatins and acetophenones using water as a reaction media and 1,4-diazabicyclo[2.2.2]octane (DABCO) as catalyst with shorter reaction time and good to excellent yield of products. 相似文献
72.
Maegawa T Kitamura Y Sako S Udzu T Sakurai A Tanaka A Kobayashi Y Endo K Bora U Kurita T Kozaki A Monguchi Y Sajiki H 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(20):5937-5943
A mild and efficient ligand-free Suzuki-Miyaura coupling reaction catalyzed by heterogeneous Pd/C was developed. Aryl bromides and triflates undergo the cross-coupling with aryl boronic acids in excellent yields without the presence of any additives in aqueous media at room temperature. Aryl vinyl boronic acids are also applicable to this coupling reaction and provide the trans-stilbene derivatives in high yields. The application of wet-type Pd/C to the coupling reaction was achieved without any loss of activity under aerobic conditions, and the reuse of Pd/C is feasible for a fifth run without significant loss of activity. Inductively coupled plasma (ICP) mass-spectrometric analysis of the filtrate from the reaction mixture of 4-bromonitrobenzene with phenylboronic acid demonstrated that the palladium metal hardly leached into the solution within the limits of the detector (<1 ppm), thus suggesting that the present Suzuki-Miyaura reaction proceeded by heterogeneous catalysis. 相似文献
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Bora Yalkinoglu 《Inventiones Mathematicae》2013,191(2):383-425
This paper has two parts. In the first part we construct arithmetic models of Bost-Connes systems for arbitrary number fields, which has been an open problem since the seminal work of Bost and Connes (Sel. Math. 1(3):411–457, 1995). In particular our construction shows how the class field theory of an arbitrary number field can be realized through the dynamics of a certain operator algebra. This is achieved by working in the framework of Endomotives, introduced by Connes, Consani and Marcolli (Adv. Math. 214(2):761–831, 2007), and using a classification result of Borger and de Smit (arXiv:1105.4662) for certain Λ-rings in terms of the Deligne-Ribet monoid. Moreover the uniqueness of the arithmetic model is shown by Sergey Neshveyev in an appendix. In the second part of the paper we introduce a base-change functor for a class of algebraic endomotives and construct in this way an algebraic refinement of a functor from the category of number fields to the category of Bost-Connes systems, constructed recently by Laca, Neshveyev and Trifkovic (arXiv:1010.4766). 相似文献
75.
Sezgin Bakırdere Selin Bora E. Gülhan Bakırdere Fırat Aydın Yasin Arslan O. Tarık Komesli Işıl Aydın Emrah Yıldırım 《Central European Journal of Chemistry》2012,10(3):675-685
Carcinogenic and mutagenic properties of aflatoxin species are known in literature. Their intake over a long time period might
be health-dangerous for human even at trace levels. It is well known that different foodstuffs can be contaminated by aflatoxin
species through growing and storage. Due to the serious health effects, sensitive determination of aflatoxin species in any
matrices related with the human being is very crucial at trace levels. In literature, there are sensitive techniques to analyze
the different samples for the contents of their aflatoxin species. Each technique has some advantages and disadvantages over
the other techniques. This review aims to summarize the different health effects of aflatoxin species, development of analytical
techniques and applications of developed techniques in a variety of matrices.
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Some unusual and unexplained events (the so-called Kolar events) were interpreted in Pramana – J. Phys. 82, 609 (2014). This article is a corrigendum to it. 相似文献
79.
Geetika Borah Devajani Boruah Gayatri Sarmah Saitanya K. Bharadwaj Utpal Bora 《应用有机金属化学》2013,27(12):688-694
The reaction of N‐methylimidazole (N‐MeIm) and N‐butylimidazole (N‐BuIm) with the complexes [PdCl2(PPh2py–P,N)] and [PdCl2(PPh2Etpy–P,N)] in the presence of NH4PF6 under N2 at room temperature afforded four new cationic Pd(II) complexes [PdCl(PPh2py–P,N)(N‐MeIm)](PF6) ( 1 ), [PdCl(PPh2py–P,N)(N‐BuIm)](PF6) ( 2 ), [PdCl(PPh2Etpy–P,N)(N‐MeIm)](PF6) ( 4 ) and [PdCl(PPh2Etpy‐P,N)(N‐BuIm)](PF6) ( 5 ) in good yields, where PPh2py is 2‐(diphenylphosphino)pyridine and PPh2Etpy is 2‐{2‐(diphenylphosphino)ethyl}pyridine). The complexes were fully characterized. The catalytic activities of these complexes were investigated for Suzuki–Miyaura cross‐coupling reactions at room temperature. Complex 2 exhibited excellent activity compared to other analogs. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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